Guard band usage for wireless data transmission

ABSTRACT

Techniques for guard band usage for wireless data transmission are described. In at least some embodiments, white spaces in the radio spectrum (e.g., television (TV) white spaces) and guard bands between licensed bands of the radio spectrum are leveraged for data transmission. Based on available white spaces and service deployment in the licensed bands, various decisions can be made regarding how to leverage white spaces and guard bands for wireless data transmission.

RELATED APPLICATIONS

This application is a divisional of and claims priority to U.S. patentapplication Ser. No. 14/252,507 entitled “Guard Band Usage for WirelessData Transmission” and filed Apr. 14, 2014 which in turn claims priorityunder 35 U.S.C. §119(e) to U.S. Provisional Patent Application No.61/944,453, filed on Feb. 25, 2014 and titled “Guard Band Usage forWireless Data Transmission,” the entire disclosures of which areincorporated in their entirety by reference herein.

BACKGROUND

Many devices today utilize some form of wireless radio frequency (RF)data communication. Examples of RF communication include cellularnetworks (e.g., for cell phones), data broadband (e.g., Wi-Fi®),broadcast television, global positioning system (GPS) navigation, and soforth. Typically, different forms of RF communication use differentportions of the radio spectrum. While many portions of the radiospectrum are allocated and/or licensed for particular uses, there remainportions that are underutilized. Underutilized portions of the radiospectrum may be leveraged for various purposes, such as for unlicensedforms of RF communication. Any use of such underutilized portions,however, must avoid interference with existing licensed RFcommunications and must comply with regulatory requirements for RFcommunication.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

Techniques for guard band usage for wireless data transmission aredescribed. In at least some embodiments, white spaces in the radiospectrum (e.g., television (TV) white spaces) and guard bands betweenlicensed portions of the radio spectrum are leveraged for datatransmission.

For instance, embodiments employ a channel database that tracksavailable white spaces and notifies various wireless base stationsand/or client devices of the available white spaces. The channeldatabase may also notify wireless base stations and/or client devicesregarding whether there is service deployment in licensed bands thatoccur adjacent to guard bands in the radio spectrum. Based on availablewhite spaces and service deployment in the licensed bands, variousdecisions can be made regarding how to leverage white spaces and guardbands for wireless data transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is described with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different instances in thedescription and the figures may indicate similar or identical items.

FIG. 1 is an illustration of an environment in an example implementationthat is operable to employ techniques discussed herein in accordancewith one or more embodiments.

FIG. 2 illustrates an example implementation scenario for determiningavailable wireless channels in accordance with one or more embodiments.

FIG. 3 illustrates an example implementation scenario for determiningguard band usage for data transmission in accordance with one or moreembodiments.

FIG. 4 illustrates an example implementation scenario for determiningguard band usage for data transmission in accordance with one or moreembodiments.

FIG. 5 illustrates an example implementation scenario for determiningguard band usage for data transmission in accordance with one or moreembodiments.

FIG. 6 is a flow diagram that describes steps in a method formaintaining a channel database in accordance with one or moreembodiments.

FIG. 7 is a flow diagram that describes steps in a method fordynamically updating a channel database in accordance with one or moreembodiments.

FIG. 8 is a flow diagram that describes steps in a method fordetermining available regions for data transmission in accordance withone or more embodiments.

FIG. 9 is a flow diagram that describes steps in a method for adjustingguard band usage in accordance with one or more embodiments.

FIG. 10 is a flow diagram that describes steps in a method for adjustingguard band usage based on downlink and uplink activity in accordancewith one or more embodiments.

FIG. 11 is a flow diagram that describes steps in a method forconsidering application parameters when identifying available channelsin accordance with one or more embodiments.

FIG. 12 illustrates an example system and computing device as describedwith reference to FIG. 1, which are configured to implement embodimentsof techniques described herein.

DETAILED DESCRIPTION

Overview

Techniques for guard band usage for wireless data transmission aredescribed. In at least some embodiments, white spaces in the radiospectrum (e.g., television (TV) white spaces) and guard bands betweenlicensed portions of the radio spectrum are leveraged for datatransmission.

For instance, embodiments employ a channel database that tracksavailable white spaces and notifies various wireless base stationsand/or client devices of the available white spaces. The channeldatabase may also notify wireless base stations and/or client devicesregarding whether there is service deployment in licensed bands thatoccur adjacent to guard bands in the radio spectrum. Based on availablewhite spaces and service deployment in the licensed bands, variousdecisions can be made regarding how to leverage white spaces and guardbands for wireless data transmission.

In at least some embodiments, white spaces and/or guard bands can beleveraged to transmit wireless broadband data, such as for datatransmission as part of a wireless local area network (WLAN). The datatransmission, for example, can be performed according to the 802.11Standards for wireless data communication managed by the Institute ofElectrical and Electronics Engineers (IEEE). The 802.11 Standards areoften referred to as “Wi-Fi®”, but are referenced to herein in variousways.

In the following discussion, an example environment is first describedthat is operable to employ techniques described herein. Next, a sectionentitled “Example Implementation Scenarios” describes someimplementation scenarios involving techniques discussed herein which maybe employed in the example environment as well as in other environments.Following this, a section entitled “Example Procedures” describes someexample procedures for guard band usage for wireless data transmissionin accordance with one or more embodiments. Finally, a section entitled“Example System and Device” describes an example system and device thatare operable to employ techniques discussed herein in accordance withone or more embodiments.

Example Environment

FIG. 1 is an illustration of an environment 100 in an exampleimplementation that is operable to employ techniques for guard bandusage for wireless data transmission. Environment 100 includes a clientdevice 102 which can be embodied as any suitable device such as, by wayof example and not limitation, a smartphone, a tablet computer, aportable computer (e.g., a laptop), a desktop computer, and so forth.One of a variety of different examples of a client device 102 is shownand described below in FIG. 12.

The client device 102 of FIG. 1 is illustrated as including a clientwireless module 104, which is representative of functionality to enablethe client device 102 to communicate wirelessly with other devicesand/or entities. The client wireless module 104 can be configured toenable data communication via a variety of different wireless techniquesand protocols. Examples of such techniques and/or protocols includecellular communications (e.g. 3G, 4G, Long Term Evolution (LTE), and soforth), near field communication (NFC), short-range wireless connections(e.g., Bluetooth), local area wireless networks (e.g., one or morestandards in compliance with IEEE 802.11), wide area wireless networks(e.g., one or more standard in compliance with IEEE 802.16 or 802.22),wireless telephone networks, and so on. For instance, the clientwireless module 104 is configured to perform various aspects oftechniques for guard band usage for wireless data transmission discussedherein.

The client device 102 further includes client wireless hardware 106,which is representative of various hardware components that can beemployed to enable the client device 102 to communicate wirelessly.Examples of the client wireless hardware 106 include radio transmitters,radio receivers, various types and/or combinations of antennas,impedance matching functionality, and so on. In at least someembodiments, the client device 102 is a multi-radio device that cancommunicate via different wireless technologies and/or protocols.

Further included as part of the client device 102 are one or more devicedrivers 108, which are representative of functionality to enable theclient device 102 to interact with various devices, and vice-versa. Forinstance, the device drivers 108 can enable interaction between variousfunctionalities of the client device 102 (e.g., an operating system,applications, services, and so on) and different devices of the clientdevice 102, such as input/output (I/O) devices. The device drivers 108,for instance, can enable interaction between the client wireless module104 and the client wireless hardware 106 to enable the client device 102to transmit and receive wireless signals.

In at least some embodiments, the client device 102 is configured tocommunicate with other devices and/or entities via a communicationapplication 110. Generally, the communication application 110 isrepresentative of functionality to enable different forms ofcommunication via the client device 102. Examples of the communicationapplication 110 include a voice communication application (e.g., a Voiceover Internet Protocol (VoIP) client), a video communicationapplication, a messaging application, a content sharing application, andcombinations thereof. The communication application 110, for instance,enables different communication modalities to be combined to providediverse communication scenarios.

The environment 100 further includes a wireless base station 112, whichis representative of a radio receiver and transmitter that serves as ahub for at least some wireless portions of network(s) 114. In at leastsome embodiments, the wireless base station 112 may serve as a gatewaybetween wired and wireless portions of the network(s) 114. The wirelessbase station 112 also includes functionality for performing variousaspects of the techniques for guard band usage for wireless datatransmission discussed herein, which are discussed in detail below.According to one or more embodiments, the wireless base station 112includes functionality for wireless communication via a variety ofdifferent wireless technologies and protocols, examples of which arediscussed elsewhere herein.

Generally, the network 114 is representative of a single network or acombination of different interconnected networks. In at least someembodiments, the network 114 represents different portions of the radiospectrum that may be leveraged for wireless communication. The network114, for instance, represents radio spectrum in different frequencybands, such as ultra-high frequency (UHF), super-high frequency (SHF),and so forth. The network 114 may also represent a combination ofwireless and wired networks and may be configured in a variety of ways,such as a wide area network (WAN), a local area network (LAN), theInternet, and so forth.

The environment 100 further includes a channel database service 116,which is representative of functionality to track and/or manage variousattributes of wireless channels. The channel database service 116, forinstance, can track channel utilization for different wireless channels,e.g., whether a particular wireless channel is in use and/or isavailable to be used for wireless communication, level of channel usagefor different channels, and so forth. The channel database service 116may track and monitor various other attributes of wireless channel, suchas channel quality, signal-to-noise ratios for different channels, noisefloor in particular channels, and so forth. For example, the channeldatabase service 116 maintains a channel database 118 that stores statusinformation for different wireless channels. As further detailed below,the channel database service 116 may provide channel information fromthe channel database 118 to different entities (e.g., the wireless basestation 112 and/or the client device 102) to enable wireless channels tobe selected for wireless communication.

In at least some embodiments, the channel database service 116 receivesinformation regarding wireless channels from channel owners 120.Generally, the channel owners 120 are representative of differententities that have certain rights and/or privileges to differentportions of the radio spectrum. For instance, the channel owners 120 mayrepresent licensees of certain portions of the radio spectrum in aparticular market and/or markets, such as television networks, cellularcarriers, radio stations, and so forth. The channel owners 120 may alsorepresent entities that are granted exclusive or shared access toparticular frequency bands, such as government organizations, emergencyservices, academic and/or research entities, and so forth. Generally,licenses and privileges for access to different portions of the radiospectrum are regulated by government organizations, such as the FederalCommunications Commission (FCC) in the United States, the Office ofCommunications (OFCOM) in the United Kingdom, and so forth.

As further illustrated in the environment 100, the wireless base station112 includes an available channel database 122, which is representativeof a database of wireless channels that are available for wirelesscommunication in the network 114. The available channel database 122,for instance, can be populated with channel information received fromthe channel database service 116. In at least some embodiments,available channel information from the available channel database 122can be propagated to the client device 102 to enable a channel and/orchannels to be selected for wireless communication. Further detailsconcerning identification and selection of wireless channels arepresented below.

According to implementations discussed herein, techniques can beemployed to establish wireless data communication between the clientdevice 102 and other devices utilizing a variety of different wirelessdata communication techniques and/or protocols. For instance, channelsthat are identified in the available channel database 122 may beleveraged for wireless communication via various of the 802.11standards. This is not intended to be limiting, however, and a widevariety of different wireless techniques and protocols may be utilizedin accordance with the disclosed embodiments. Further, while certainaspects of established wireless protocols (e.g., 802.11, Wi-Fi Direct™,and so on) may be utilized in tandem with techniques discussed herein toenable wireless data communication between devices, techniques discussedherein are inventive and are not to be considered part of theseprotocols as they currently exist.

Having described an example environment in which the techniquesdescribed herein may operate, consider now a discussion of some exampleimplementation scenarios in accordance with one or more embodiments.

Example Implementation Scenarios

The following discussion describes example implementation scenarios forguard band usage for wireless data transmission in accordance with oneor more embodiments. In portions of the following discussion, referencewill be made to the environment 100 of FIG. 1.

FIG. 2 illustrates an example implementation scenario 200 fordetermining available wireless channels in accordance with one or moreembodiments.

In the scenario 200, the channel database service 116 determines that aspectrum portion 202 of the radio spectrum includes a set of availablechannels 204. In this particular example, the spectrum portion 202corresponds to a portion of the UHF region of the radio spectrum. Thisis not to be construed as limiting, however, and a variety of differentregions of the radio spectrum may be employed in accordance with theclaimed embodiments.

The channel database service 116 may determine the available channels204 in a variety of different ways. For instance, channel owners 120 forindividual of the respective available channels 204 may notify thechannel database service 116 of the available channels 204.Alternatively or additionally, the channel database service 116 mayquery the channel owners 120 as to whether their respective channels arebeing utilized. As yet another example, the channel database service 116may detect that the available channels are not being leveraged forsignal broadcasting.

As an example implementation, consider that the available channels 204corresponds to “white spaces” in the spectrum portion 202 of the radiospectrum. The available channels 204, for instance, may be licensed toparticular channel owners 120 and/or allocated for particular uses. Theavailable channels 204, however, are not currently in use. For example,the available channels 204 may occur in the 700-megahertz band thatincludes broadcast television channels. Thus, the available channels 204may correspond to discrete television channels that are licensed toparticular channel owners 120 but are not being utilized to broadcasttelevision content. In at least some embodiments, the channel owners 120for the respective available channels 204 may notify the channeldatabase service 116 as such. Channels between and/or adjacent to theavailable channels 204 may correspond to television channels that are inuse for broadcasting television content and/or other types ofinformation.

Further to the scenario 200, the channel database service 116 storeschannel identifiers 206 for the available channels 204 as part of thechannel database 118. The channel database service 116 then provides thechannel identifiers 206 to the client device 102, such as in response toa query from the client device 102 for available channels. The channelidentifiers 206 may identify the available channels 204 in various ways,such as with reference to frequency ranges for the individual availablechannels 204, channel numbers for the channels (e.g., assigned based ona regional band plan), and so forth.

In at least some embodiments, for instance, the client device 102 (e.g.,via the client wireless module 104) can query the channel databaseservice 116 for available channels on a periodic basis (e.g., every 24hours) and/or in response to various events, such as an initiation of acommunication session via the communication application 110. The clientdevice 102 stores the channel identifiers 206 as part of a channel set208 that generally corresponds to channels that are available to theclient device 102 for wireless communication. The client device 102 mayutilize one or more channels identified in the channel set 208 toinitiate and/or participate in wireless data communication.

FIG. 3 illustrates an example implementation scenario 300 fordetermining guard band usage for data transmission in accordance withone or more embodiments.

The scenario 300 includes the spectrum portion 202 of the radio spectrumintroduced above with reference to FIG. 2. In addition to the availablechannels 204, the spectrum portion 202 includes a first guard band 302and a second guard band 304. Generally, the guard bands 302, 304represent unused regions of the radio spectrum that separate differentactive regions of the radio spectrum. The guard bands 302, 304, forexample, serve as buffers to minimize and/or prevent interferencebetween adjacent active portions of the radio spectrum.

In the scenario 300, the guard band 302 separates a television region306 of the spectrum portion 202 (e.g., where the available channels 204occur) from a downlink portion 308. The guard band 304 separates thedownlink portion 308 from an uplink portion 310. In at least someembodiments, the guard band 304 represents a duplex gap between thedownlink portion 308 and the uplink portion 310.

Generally, the downlink portion 308 is utilized for downlinkcommunication, such as from a cellular base station to the client device102. The uplink portion 310 is utilized for uplink communication, suchas from the client device 102 to a base station and/or other entity. Inat least some embodiments, the downlink portion 308 and the uplinkportion 310 correspond to LTE downlink and uplink portions,respectively. These examples are not to be construed as limiting,however, and the guard bands 302, 304 may occur in other portions of theradio spectrum not specifically discussed herein.

Also illustrated is that in at least some embodiments, the channeldatabase service 116 may track whether there is service deployment inthe regions adjacent to the guard bands 302, 304, e.g., in the downlinkportion 308 and the uplink portion 310. For instance, in at least somegeographical regions and/or markets, the infrastructure for deploymentof service in the downlink portion 308 and the uplink portion 310 maynot be in place or may not be active. Thus, in such regions, thedownlink portion 308 and the uplink portion 310 may not be in use.

In this particular example, the channel database 118 indicates thatthere is deployment in the downlink portion 308 and the uplink portion310. Thus, when the client device 102 utilizes one or more of the guardbands 302, 304 for data transmission, the client device 102 will monitorfor activity in the downlink portion 308 and the uplink portion 310.

In other example scenarios, however, there may not be deployment in thedownlink portion 308 and the uplink portion 310. In these scenarios, theclient device may not monitor for activity in the downlink portion 308and the uplink portion 310, and thus may make full use of the guardbands 302, 304 for transmitting signals.

Further to the scenario 300, the client device 102 determines variousattributes of the downlink portion 308 and the uplink portion 310 and,based on these attributes, decides whether and/or how the guard bands302, 304 may be utilized for wireless communication. For instance, theclient device 102 can detect whether there is downlink traffic in thedownlink portion 308 and/or uplink traffic in the uplink portion 310and, based on whether there is traffic in the respective portions,decide how the guard bands 302, 304 may be leveraged as channels forwireless data communication. Example ways of optimizing usage of theguard bands 302, 304 for wireless communication are discussed below.

Based on its analysis of the downlink portion 308 and/or the uplinkportion 310, the client device 102 updates the channel set 208 tospecify whether and/or how the downlink portion 308 and/or the uplinkportion 310 may be utilized for wireless communication. Thus, thechannel set 208 can identify various portions of the radio spectrum thatare available for wireless communication, such as the available channels204, the guard bands 302, 304, and/or other channels. The client device102 (e.g., the client wireless module 104) can consider various criteriain determining which of the channels to select when engaging in wirelessdata communication. Examples of such criteria include channel quality(e.g., signal-to-noise (S/N) ratio), channel congestion, and so forth.

FIG. 4 illustrates an example implementation scenario 400 fordetermining guard band usage for data transmission in accordance withone or more embodiments.

The upper portion of the scenario 400 illustrates a guard band 402which, in at least some embodiments, represents an implementation of oneor more of the guard bands 302, 304 introduced above. Adjacent to theguard band 402 is a licensed region 404 and a licensed region 406, whichrepresent regions of the radio spectrum that are licensed and/orallocated for particular purposes. In at least some embodiments, thelicensed regions 404, 406 represent implementations of the downlinkportion 308 and the uplink portion 310, respectively, which wereintroduced above.

A prerequisite on usage of the guard band 402 is that the usage avoidsinterference with radio traffic in the licensed regions 404, 406. Thus,embodiments employ various techniques to ascertain whether there isactivity in one or more of the licensed regions 404, 406. Based onwhether traffic is detected in one or more of the licensed regions 404,406 (e.g., uplink and/or downlink traffic), usage of the guard band 402can be modified.

In the upper portion of the scenario 400, little or no traffic isdetected in the licensed regions 404, 406. Thus, the guard band 402 maybe leveraged in various ways, such as for a communication channel 408.Generally, the communication channel 408 represents a discrete frequencyband that can be utilized to transmit and/or receive data, such as forwireless broadband. In this particular example, the communicationchannel 408 is centered in the guard band 402. Although a singlecommunication channel 408 is illustrated, embodiments may employmultiple communication channels within a guard band and/or a whitespace.

Continuing to the lower portion of the scenario 400, consider thattraffic is detected in the licensed region 404 but little or no trafficis detected in the licensed region 406. Traffic in the licensed region404, for instance, corresponds to downlink traffic, such as from acellular base station to a cellular device, e.g., the client device 102.The presence and/or level of traffic in a particular region can bedetected in various ways. For instance, the client device 102 itself candetect the traffic. Alternatively or additionally, a remote service candetect the traffic, such as the wireless base station 112 and/or thechannel database service 116. In embodiments where a remote servicedetects the presence and/or level of traffic, the remote service cannotify a client device (e.g., the client device 102) of the presenceand/or level of traffic.

Further to the scenario 400, in response detecting traffic in thelicensed region 404 but little or no traffic in the licensed region 406,usage of the guard band 402 for a communication channel 408 is adjustedaccordingly. As illustrated, for instance, the center frequency of thecommunication channel 408 is increased such that the communicationchannel 408 is moved away from the licensed region 404 and towards thelicensed region 406. According to various embodiments, this provides abuffer region 410 that minimizes or prevents interference between thecommunication channel 408 and the signal activity in the licensed region404.

FIG. 5 illustrates another example implementation scenario 500 fordetermining guard band usage for data transmission in accordance withone or more embodiments. In at least some embodiments, the scenario 500represents an extension of the scenario 400 discussed above.

In the upper portion of the scenario 500, consider that thecommunication channel 408 is being used to transmit a signal 502. In atleast some embodiments, the signal 502 is an orthogonalfrequency-division multiplexing (OFDM) signal that utilizes subcarriersignals. The signal 502, for instance, can be implemented as a WiFi™OFDM signal that is divided into 52 subcarriers signals. The number ofsubcarriers illustrated as part of the signal 502 is presented forpurpose of example only, and it is to be appreciated that any suitablenumber of subcarriers may be employed.

Consider now that traffic is then detected in the licensed region 406 aswell as the licensed region 404. In response to detecting the traffic inthe licensed region 406, at least some subcarriers of the signal 502 aremodified.

For example, proceeding to the lower portion of the scenario 500, theouter subcarriers 504 a, 504 b of the signal 502 are attenuated.Transmission power for the outer subcarriers 504 a, 504 b, for instance,is reduced, such as by a pre-specified amount. Further, transmissionpower of the inner subcarriers 506 is increased, such as by apre-specified amount. In at least some embodiments, increasing thetransmission power of the inner subcarriers 506 is optional.

According to one or more embodiments, the outer subcarriers 504 a, 504 bmay be attenuated and/or the inner subcarriers 506 amplified withoutaltering the bandwidth of the communication channel 408 or the signal502. For instance, attenuation of the outer subcarriers 504 a, 504 b maybe proportion to amplification of the inner subcarriers 506, andvice-versa.

Attenuation of the outer portions of the signal 502 (e.g., the outersubcarriers 504 a, 504 b) decreases the amount of interference that mayoccur between the signal 502 and signals in the licensed band 406. By somodifying the signal 502, the communication channel 408 may continue tobe used for transmitting communication data while reducing interferencewith signals in adjacent bands.

Having discussed some example implementation scenarios, consider nowsome example procedures in accordance with one or more embodiments.

Example Procedures

FIG. 6 is a flow diagram that describes steps in a method formaintaining a channel database in accordance with one or moreembodiments.

Step 600 ascertains available white spaces and guard bands in a regionof the radio spectrum. The channel database service 116, for instance,identifies guard bands and white space channels in a particulargeographical region. The channel database service 116 can identify guardbands and white spaces in a variety of ways. For instance, channelowners 120 for the white spaces can notify the channel database service116 that their respective channels are not being utilized. Alternativelyor additionally, the channel database service 116 can query channelowners 120 as to whether there is deployment in their respectivechannels. The channel database service 116 may also scan a region of theradio spectrum to identify available guard bands and/or white spaces.Other ways of identifying white spaces not expressly discussed hereinmay be employed.

Step 602 determines whether there is service deployment in a licensedband adjacent to a guard band. With reference to the implementationscenarios discussed above, the channel database service 116 candetermine whether there is service deployment that utilizes the downlinkportion 308 and the uplink portion 310. For instance, in an exampleimplementation where the downlink portion 308 and the uplink portion 310are in a region of the spectrum allocated for LTE deployment, thechannel database service 116 can ascertain whether there is actual LTEservice deployment in that region.

Step 604 provides a notification of identifiers for the available whitespaces and guard bands and whether there is service deployment in thelicensed band. For instance, the channel database service 116 notifiesthe wireless base station 112 and/or the client device 102 of availablechannels, e.g., the available channels 204 introduced above. The channeldatabase service 116 may further provide a notification as to whetherthere is service deployment in the downlink portion 308 and the uplinkportion 310.

In at least some embodiments, white space availability may bedynamically updated in various ways. For instance, consider thefollowing example procedure.

FIG. 7 is a flow diagram that describes steps in a method fordynamically updating a channel database in accordance with one or moreembodiments.

Step 700 receives an indication of a change to white space availability.For instance, the channel database service 116 may periodically querythe channel owners 120 regarding availability of their respectivechannels. Thus, additional white spaces may become available if achannel that was previously being used ceases being used, e.g., goes“off the air.” Further, a channel that was previously identified asbeing a white space may go into use (e.g., for broadcast television),and thus its identification as a white space may be withdrawn.

Step 702 provides a notification of the change to white spaceavailability. For instance, the channel database service 116 notifiesthe wireless base station 112 and/or the client device 102 of thechange, e.g., that an additional white space is available and/or that apreviously-available white space is no longer available.

FIG. 8 is a flow diagram that describes steps in a method fordetermining available regions for data transmission in accordance withone or more embodiments.

Step 800 submits a query for available wireless channels in a particularregion. For instance, the client device 102 queries the wireless basestation 112 for available channels.

Step 802 receives identifiers for available white spaces and guard bandsin response to the query. The client device 102, for example, receivesidentifiers for white space channels and/or guard bands that areavailable in the region.

Step 804 utilizes a guard band and at least one of the available whitespaces for wireless data transmission. The client device 102, forexample, can transmit data in one or more white spaces as well as one ormore guard bands. In at least some embodiments, the data can betransmitted as part of a communication session, such as managed by thecommunication application 110.

According to one or more embodiments, which white space(s) to select fordata transmission can depend on attributes of the individual whitespaces. For instance, white spaces with a lower noise floor can bepreferred over those with a higher noise floor. Further, white spaceswith less traffic (e.g., from other devices) can be preferred over thosewith more traffic. As another example, white spaces that are adjacentother white spaces can be preferred over those that are adjacent activechannels, e.g., channels that are being used for television broadcastingand so forth.

Step 806 determines whether there is service deployment in a licensedband adjacent to the guard band. For instance, the client device 102 mayreceive information from the client database service 116 indicatingwhether there is service deployment in the licensed band.

Alternatively or additionally, the client device 102 may monitor foractivity (e.g., downlink and/or uplink activity) in the licensed band.If activity is detected, the client device 102 may determine that thereis service deployment in the licensed band. Otherwise, if no activity isdetected (e.g., over a specified time period), the client device 102 maydetermine that there is no service deployment in the licensed band.

If there is service deployment in the licensed band adjacent to theguard band (“Yes”), step 808 monitors for activity in the licensed band.The client device 102, for example, monitors for uplink and/or downlinkactivity in the licensed band while transmitting data in the guard band.As detailed herein, if activity in the licensed band is detected, usageof the guard band for data transmission can be modified in various ways.

If there is no service deployment in the licensed band adjacent to theguard band (“No”), step 810 utilizes the guard band for datatransmission without monitoring for activity in the licensed band. Bynot having to monitor for activity in the licensed band, powerconsumption can be reduced and various computing resources can beconserved. Further, knowing that there is no service deployment in thelicensed band enables the guard band to be more fully utilized for datatransmission.

FIG. 9 is a flow diagram that describes steps in a method for adjustingguard band usage in accordance with one or more embodiments. The method,for instance, is an extension of the method described above withreference to FIG. 8.

Step 900 detects signal activity in a licensed region adjacent to aguard band. The client device 102, for example, detects the signalactivity, such as uplink and/or downlink activity. In at least someembodiments, the signal activity may be detected prior to initiating useof the guard band for data transmission, and/or while the guard band isbeing used for data transmission. The signal activity, for example, maybe detected while a communication session is in progress that isutilizing the guard band for data transmission.

Step 902 adjusts a signal for transmission in the guard band based onthe detected signal activity. The frequency range used to transmit thesignal, for instance, can be increased or decreased away from thelicensed region, such as discussed above with reference to FIG. 4.Alternatively or additionally, some subcarrier channels of the signalcan be attenuated to avoid interference with the detected signalactivity, such as discussed above with reference to FIG. 5.

In at least some embodiments, center frequency adjustment and subcarrierattenuation may be used in combination to modify a signal fortransmission in a guard band. For instance, when signal activity isdetected in a first region adjacent to a guard band, the center offrequency of a signal being transmitted in the guard band can be movedaway from the first region. Then, when signal activity is detected at asecond region adjacent the guard band, exterior subcarriers of thesignal being transmitted in the guard band can be attenuated to reduceinterference with the signal activity in the second region. Thus, thecombination of center frequency adjusting and subcarrier attenuationprovides a flexible way of responding the changing conditions whenutilizing a guard band for data transmission.

FIG. 10 is a flow diagram that describes steps in a method for adjustingguard band usage based on downlink and uplink activity in accordancewith one or more embodiments. The method, for instance, describes adetailed implementation of the method described above with reference toFIG. 9.

Step 1000 identifies a guard band between a downlink band and an uplinkband for transmitting a wireless signal. The guard band, for instance,can be identified by the client device 102 and/or the channel databaseservice 116. In at least some embodiments, the guard band may be aduplex gap between the downlink band and the uplink band, such asbetween an LTE downlink band and an LTE uplink band.

Step 1002 shifts the wireless signal away from the downlink band inresponse to detecting downlink activity in the downlink band. The clientdevice 102, for instance, can shift the center frequency of the wirelesssignal away from the downlink band and towards the uplink band inresponse to detecting the downlink activity. See, for example, theimplementation scenario 400 discussed above.

Step 1004 attenuates outer subcarriers of the wireless signal inresponse to detecting uplink activity in the uplink band. For instance,the client device 102 can reduce transmission power of outer subcarriersof the wireless signal, such as illustrated above in the implementationscenario 500. In at least some embodiments, attenuating the outersubcarriers reduces interference between the wireless signal and theuplink activity.

Step 1006 shifts the wireless signal toward the downlink band inresponse to detecting a pause in downlink activity in the downlink band.For instance, while monitoring activity in the downlink band, the clientdevice 102 can detect that downlink activity has stopped for a specifiedperiod of time. In response, the client device 102 shifts the centerfrequency of the wireless signal toward the downlink band, e.g., awayfrom the uplink band. Optionally, the client device 102 may also stopattenuating the outer subcarriers of the wireless signal. Thus, signaltransmission can be dynamically adjusted in various ways to accommodatechanges in downlink and/or uplink activity and to optimize use ofavailable channels.

FIG. 11 is a flow diagram that describes steps in a method forconsidering application parameters when identifying available channelsin accordance with one or more embodiments.

Step 1100 receives a request for a transmission channel for transmittingdata for a specific application. The channel database service 116, forinstance, receives a request from the client device 102 (e.g., via thewireless base station 112) for a transmission channel from transmittingdata for the communication application 110.

Step 1102 selects a transmission channel based on transmissionparameters for the specific application. In at least some embodiments,the transmission channel is selected from available white spaces andguard bands in a particular region. For example, the channel databaseservice 116 may be preconfigured to identify channels that satisfycertain transmission parameters for the communication application 110.Examples of such transmission parameters include a noise floor levelthreshold (e.g., a maximum allowed noise floor), minimum S/N ratio, amaximum allowed amount of channel traffic, minimum channel bandwidth,and so forth.

Step 1104 provides a notification identifying the transmission channel.The channel database service 116 and/or the wireless base station 112,for example, notifies the client device 102 of one or more channels(e.g., white spaces, guard bands, and so forth) that correspond to thetransmission parameters for the communication application 110. Thus, thechannel(s) may be leveraged to transmit and/or receive data for thecommunication application 110.

Having discussed some example procedures, consider now a discussion ofan example system and device in accordance with one or more embodiments.

Example System and Device

FIG. 12 illustrates an example system generally at 1200 that includes anexample computing device 1202 that is representative of one or morecomputing systems and/or devices that may implement various techniquesdescribed herein. For example, the client device 102 discussed abovewith reference to FIG. 1 can be embodied as the computing device 1202.The computing device 1202 may be, for example, a server of a serviceprovider, a device associated with the client (e.g., a client device),an on-chip system, and/or any other suitable computing device orcomputing system.

The example computing device 1202 as illustrated includes a processingsystem 1204, one or more computer-readable media 1206, and one or moreI/O Interfaces 1208 that are communicatively coupled, one to another.Although not shown, the computing device 1202 may further include asystem bus or other data and command transfer system that couples thevarious components, one to another. A system bus can include any one orcombination of different bus structures, such as a memory bus or memorycontroller, a peripheral bus, a universal serial bus, and/or a processoror local bus that utilizes any of a variety of bus architectures. Avariety of other examples are also contemplated, such as control anddata lines.

The processing system 1204 is representative of functionality to performone or more operations using hardware. Accordingly, the processingsystem 1204 is illustrated as including hardware element 1210 that maybe configured as processors, functional blocks, and so forth. This mayinclude implementation in hardware as an application specific integratedcircuit or other logic device formed using one or more semiconductors.The hardware elements 1210 are not limited by the materials from whichthey are formed or the processing mechanisms employed therein. Forexample, processors may be comprised of semiconductor(s) and/ortransistors (e.g., electronic integrated circuits (ICs)). In such acontext, processor-executable instructions may beelectronically-executable instructions.

The computer-readable media 1206 is illustrated as includingmemory/storage 1212. The memory/storage 1212 represents memory/storagecapacity associated with one or more computer-readable media. Thememory/storage 1212 may include volatile media (such as random accessmemory (RAM)) and/or nonvolatile media (such as read only memory (ROM),Flash memory, optical disks, magnetic disks, and so forth). Thememory/storage 1212 may include fixed media (e.g., RAM, ROM, a fixedhard drive, and so on) as well as removable media (e.g., Flash memory, aremovable hard drive, an optical disc, and so forth). Thecomputer-readable media 1206 may be configured in a variety of otherways as further described below.

Input/output interface(s) 1208 are representative of functionality toallow a user to enter commands and information to computing device 1202,and also allow information to be presented to the user and/or othercomponents or devices using various input/output devices. Examples ofinput devices include a keyboard, a cursor control device (e.g., amouse), a microphone (e.g., for implementing voice and/or spoken input),a scanner, touch functionality (e.g., capacitive or other sensors thatare configured to detect physical touch), a camera (e.g., which mayemploy visible or non-visible wavelengths such as infrared frequenciesto detect movement that does not involve touch as gestures), and soforth. Examples of output devices include a display device (e.g., amonitor or projector), speakers, a printer, a network card,tactile-response device, and so forth. Thus, the computing device 1202may be configured in a variety of ways as further described below tosupport user interaction.

Various techniques may be described herein in the general context ofsoftware, hardware elements, or program modules. Generally, such modulesinclude routines, programs, objects, elements, components, datastructures, and so forth that perform particular tasks or implementparticular abstract data types. The terms “module,” “functionality,” and“component” as used herein generally represent software, firmware,hardware, or a combination thereof. The features of the techniquesdescribed herein are platform-independent, meaning that the techniquesmay be implemented on a variety of commercial computing platforms havinga variety of processors.

An implementation of the described modules and techniques may be storedon or transmitted across some form of computer-readable media. Thecomputer-readable media may include a variety of media that may beaccessed by the computing device 1202. By way of example, and notlimitation, computer-readable media may include “computer-readablestorage media” and “computer-readable signal media.”

“Computer-readable storage media” may refer to media and/or devices thatenable persistent storage of information in contrast to mere signaltransmission, carrier waves, or signals per se. Computer-readablestorage media do not include signals per se. The computer-readablestorage media includes hardware such as volatile and non-volatile,removable and non-removable media and/or storage devices implemented ina method or technology suitable for storage of information such ascomputer readable instructions, data structures, program modules, logicelements/circuits, or other data. Examples of computer-readable storagemedia may include, but are not limited to, RAM, ROM, EEPROM, flashmemory or other memory technology, CD-ROM, digital versatile disks (DVD)or other optical storage, hard disks, magnetic cassettes, magnetic tape,magnetic disk storage or other magnetic storage devices, or otherstorage device, tangible media, or article of manufacture suitable tostore the desired information and which may be accessed by a computer.

“Computer-readable signal media” may refer to a signal-bearing mediumthat is configured to transmit instructions to the hardware of thecomputing device 1202, such as via a network. Signal media typically mayembody computer readable instructions, data structures, program modules,or other data in a modulated data signal, such as carrier waves, datasignals, or other transport mechanism. Signal media also include anyinformation delivery media. The term “modulated data signal” means asignal that has one or more of its characteristics set or changed insuch a manner as to encode information in the signal. By way of example,and not limitation, communication media include wired media such as awired network or direct-wired connection, and wireless media such asacoustic, RF, infrared, and other wireless media.

As previously described, hardware elements 1210 and computer-readablemedia 1206 are representative of instructions, modules, programmabledevice logic and/or fixed device logic implemented in a hardware formthat may be employed in some embodiments to implement at least someaspects of the techniques described herein. Hardware elements mayinclude components of an integrated circuit or on-chip system, anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA), a complex programmable logic device (CPLD), and otherimplementations in silicon or other hardware devices. In this context, ahardware element may operate as a processing device that performsprogram tasks defined by instructions, modules, and/or logic embodied bythe hardware element as well as a hardware device utilized to storeinstructions for execution, e.g., the computer-readable storage mediadescribed previously.

Combinations of the foregoing may also be employed to implement varioustechniques and modules described herein. Accordingly, software,hardware, or program modules and other program modules may beimplemented as one or more instructions and/or logic embodied on someform of computer-readable storage media and/or by one or more hardwareelements 1210. The computing device 1202 may be configured to implementparticular instructions and/or functions corresponding to the softwareand/or hardware modules. Accordingly, implementation of modulesdiscussed herein as software may be achieved at least partially inhardware, e.g., through use of computer-readable storage media and/orhardware elements 1210 of the processing system. The instructions and/orfunctions may be executable/operable by one or more articles ofmanufacture (for example, one or more computing devices 1202 and/orprocessing systems 1204) to implement techniques, modules, and examplesdescribed herein.

As further illustrated in FIG. 12, the example system 1200 enablesubiquitous environments for a seamless user experience when runningapplications on a personal computer (PC), a television device, and/or amobile device. Services and applications run substantially similar inall three environments for a common user experience when transitioningfrom one device to the next while utilizing an application, playing avideo game, watching a video, and so on.

In the example system 1200, multiple devices are interconnected througha central computing device. The central computing device may be local tothe multiple devices or may be located remotely from the multipledevices. In one embodiment, the central computing device may be a cloudof one or more server computers that are connected to the multipledevices through a network, the Internet, or other data communicationlink.

In one embodiment, this interconnection architecture enablesfunctionality to be delivered across multiple devices to provide acommon and seamless experience to a user of the multiple devices. Eachof the multiple devices may have different physical requirements andcapabilities, and the central computing device uses a platform to enablethe delivery of an experience to the device that is both tailored to thedevice and yet common to all devices. In one embodiment, a class oftarget devices is created and experiences are tailored to the genericclass of devices. A class of devices may be defined by physicalfeatures, types of usage, or other common characteristics of thedevices.

In various implementations, the computing device 1202 may assume avariety of different configurations, such as for computer 1214, mobile1216, and television 1218 uses. Each of these configurations includesdevices that may have generally different constructs and capabilities,and thus the computing device 1202 may be configured according to one ormore of the different device classes. For instance, the computing device1202 may be implemented as the computer 1214 class of a device thatincludes a personal computer, desktop computer, a multi-screen computer,laptop computer, netbook, and so on.

The computing device 1202 may also be implemented as the mobile 1216class of device that includes mobile devices, such as a mobile phone,portable music player, portable gaming device, a tablet computer, amulti-screen computer, and so on. The computing device 1202 may also beimplemented as the television 1218 class of device that includes deviceshaving or connected to generally larger screens in casual viewingenvironments. These devices include televisions, set-top boxes, gamingconsoles, and so on.

The techniques described herein may be supported by these variousconfigurations of the computing device 1202 and are not limited to thespecific examples of the techniques described herein. For example,functionalities discussed with reference to the client device 102, thewireless base station 112, and/or the channel database service 116 maybe implemented all or in part through use of a distributed system, suchas over a “cloud” 1220 via a platform 1222 as described below.

The cloud 1220 includes and/or is representative of a platform 1222 forresources 1224. The platform 1222 abstracts underlying functionality ofhardware (e.g., servers) and software resources of the cloud 1220. Theresources 1224 may include applications and/or data that can be utilizedwhile computer processing is executed on servers that are remote fromthe computing device 1202. Resources 1224 can also include servicesprovided over the Internet and/or through a subscriber network, such asa cellular or Wi-Fi™ network.

The platform 1222 may abstract resources and functions to connect thecomputing device 1202 with other computing devices. The platform 1222may also serve to abstract scaling of resources to provide acorresponding level of scale to encountered demand for the resources1224 that are implemented via the platform 1222. Accordingly, in aninterconnected device embodiment, implementation of functionalitydescribed herein may be distributed throughout the system 1200. Forexample, the functionality may be implemented in part on the computingdevice 1202 as well as via the platform 1222 that abstracts thefunctionality of the cloud 1220.

Discussed herein are a number of methods that may be implemented toperform techniques discussed herein. Aspects of the methods may beimplemented in hardware, firmware, or software, or a combinationthereof. The methods are shown as a set of blocks that specifyoperations performed by one or more devices and are not necessarilylimited to the orders shown for performing the operations by therespective blocks. Further, an operation shown with respect to aparticular method may be combined and/or interchanged with an operationof a different method in accordance with one or more implementations.Aspects of the methods can be implemented via interaction betweenvarious entities discussed above with reference to the environment 100.

Conclusion

Techniques for guard band usage for wireless data transmission aredescribed. Although embodiments are described in language specific tostructural features and/or methodological acts, it is to be understoodthat the embodiments defined in the appended claims are not necessarilylimited to the specific features or acts described. Rather, the specificfeatures and acts are disclosed as example forms of implementing theclaimed embodiments.

What is claimed is:
 1. A system comprising: one or more processors; andone or more computer-readable storage media storing computer-executableinstructions that are executable by the one or more processors toperform operations including: ascertaining available white spaces in aregion of the radio spectrum; determining whether there is servicedeployment in a licensed band adjacent to a guard band in the region,said determining including determining that there is not infrastructurein place for deployment of service in the licensed band; and providing anotification of identifiers for the available white spaces and anindication that there is not infrastructure in place for servicedeployment in the licensed band to enable a client device to utilize theguard band and one or more of the white spaces for wireless datatransmission.
 2. A system as described in claim 1, wherein the guardband occurs between a television band and a downlink band.
 3. A systemas described in claim 1, wherein the licensed band comprises one or moreof a downlink band or an uplink band adjacent to the guard band.
 4. Asystem as described in claim 1, wherein the operations further comprise:receiving an indication of a change to white space availability in theregion; and providing a notification of the change to the white spaceavailability to the client device.
 5. A system as described in claim 4,wherein the change comprises one or more of: at least one additionalwhite space is available; or a previously-available white space is nolonger available.
 6. A system as described in claim 1, wherein theoperations further comprise: receiving a request for a transmissionchannel for transmitting data for a specific application; selecting oneor more transmission channels based on transmission parameters for thespecific application, the one or more transmission channels beingselected from the available white spaces and the guard band; andproviding a notification identifying the one or more transmissionchannels.
 7. A system as described in claim 6, wherein the transmissionparameters comprise one or more of a noise floor threshold, a maximumallowed amount of channel traffic, or a minimum channel bandwidth forthe specific application.
 8. A system as described in claim 1, whereinsaid ascertaining is performed in response to a query from the clientdevice for an available wireless channel in a particular geographicalregion.
 9. A method comprising: ascertaining an available white space ina region of the radio spectrum; determining whether there is servicedeployment in a licensed band adjacent to a guard band in the region,said determining including determining that there is not infrastructurein place for deployment of service in the licensed band; and providing anotification of an identifier for the available white space and anindication that there is not infrastructure in place for servicedeployment in the licensed band to enable a client device to utilize theguard band and the white space for wireless data transmission.
 10. Amethod as described in claim 9, wherein the licensed band comprises oneor more of a downlink band or an uplink band adjacent to the guard band.11. A method as described in claim 9, further comprising: receiving anindication of a change to white space availability in the region; andproviding a notification of the change to the white space availabilityto the client device.
 12. A method as described in claim 11, wherein thechange comprises an indication that the white space is no longeravailable.
 13. A method as described in claim 9, further comprising:receiving a request for a transmission channel for transmitting data fora specific application; selecting one or more transmission channelsbased on transmission parameters for the specific application, the oneor more transmission channels being selected from the white space andthe guard band; and providing a notification identifying the one or moretransmission channels.
 14. A method as described in claim 13, whereinthe transmission parameters comprise one or more of a noise floorthreshold, a maximum allowed amount of channel traffic, or a minimumchannel bandwidth for the specific application.
 15. A method asdescribed in claim 9, wherein said ascertaining is performed in responseto a query from the client device for an available wireless channel in aparticular geographical region.
 16. A method comprising: receiving aquery from a client device for an available wireless channel in aparticular geographical region; ascertaining an available white space inthe particular geographical region; determining whether there is servicedeployment in a licensed band adjacent to a guard band in a particularportion of radio spectrum in which the available white space resides,said determining including determining there is not infrastructure inplace for deployment of service in the licensed band; and providing anotification of an identifier for the available white space and anindication that there is not infrastructure in place for servicedeployment in the licensed band to enable a client device to utilize theguard band and the white space for wireless data transmission.
 17. Amethod as described in claim 16, wherein said ascertaining is based onthe available white space meeting a transmission parameter for aspecific application.
 18. A method as described in claim 16, furthercomprising: receiving an indication of a change to white spaceavailability in the region; and providing a notification of the changeto the white space availability to the client device.
 19. A method asdescribed in claim 18, wherein the change comprises one or more of: thewhite space is no longer available; or at least one additional whitespace is available.
 20. A method as described in claim 16, wherein saiddetermining comprises determining that there is service deployment inthe licensed band, and where the notification indicates that there isservice deployment in the licensed band.